两种基于吡啶/芴的有机配体的设计、合成、表征及其光学性质

Design, Synthesis, Characteristics and Optical Properties of Two Pyridine/Fluorene Based Organic Ligands

  • 摘要: 合成了两种基于吡啶/芴的有机配体9-(2-氯-3-吡啶基)-9-羟基芴(2-ClPyFOH)和9-(6-溴2-吡啶基)-9-羟基芴(6-BrPyFOH).通过质谱和核磁对这些化合物的结构进行了详细表征.9-(2-吡啶基)-9-羟基芴(PyFOH)、6-BrPyFOH和2-ClPyFOH在环己烷、二氯甲烷、乙酸乙酯、乙醇和乙腈溶液中的最大吸收峰分别是268/275/275、275/275/275、268/274/271、268/274/271和268/275/271 nm.结果表明:除乙酸乙酯外,这些化合物的吸收光谱在同一溶剂中随着吡啶上卤素取代基的吸电子能力增强光谱红移.在这5种溶剂中,3种化合物的发射光谱的发射峰分别为313/356/356、327/358/365、359/367/312、316/316/401和386/377/438 nm.PyFOH和6-BrPyFOH的发射光谱同在其他极性较低的溶剂中相比,在乙醇溶剂中发生蓝移,这可能是由吡啶基团上n-π*电子转移态的溶剂效应所引起的.2-ClPyFOH的发射光谱除乙酸乙酯外,随着溶剂极性的增加光谱发生红移.在吡啶2-位和6-位的氯原子和溴原子将赋予这些配体具有不同的结构从而具有不同的功能和光学性质.

     

    Abstract: Two pyridine/fluorene-based organic ligands 9-(2-chloropyridin-2-yl)-fluoren-9-ol (2-ClPyFOH) and 9-(6-bromopyridin-2-yl)-fluoren-9-ol (6-BrPyFOH) were synthesized successfully. The structures of the compounds were characterized detailedly by mass spectra and nuclear magnetic resonance. The most intense absorption peaks of 9-(pyridyl-2-yl)-fluoren-9-ol (PyFOH), 6-BrPyFOH, 2-ClPyFOH are 268/275/275, 275/275/275, 268/274/271, 268/274/271, and 268/275/271 nm in cyclohexane, dichloromethane, acetic ether, ethanol and acetonitrile, respectively, which shows the UV-vis of the compounds are red-shifted as the electron-withdrawing ability of halogenated pyridine segments in these solvents except acetic ether. The photoluminescence (PL) spectra peaks of the three compounds are 313/356/356, 327/358/365, 359/367/312, 316/316/401, and 386/377/438 nm in the five solvents, respectively. The PL spectra of PyFOH and 6-BrPyFOH are blue-shifted in ethanol solution compared to those in other lower polarity solvents, which is probably induced by their n-π* electronic transition upon solvation derived from the pyridine segment. The PL spectra of 2-ClPyFOH is red-shifted in these solvents as the solvents polarity increasing except acetic ether. The bromine and chlorine at the 2-and 6-position of pyridine group would endow the ligands with different function units to provide various structures with especial characteristics.

     

/

返回文章
返回